Structural investigation of II–VI compound semiconductor quantum wires using triple-axis X-ray diffractometry

Abstract

Corrugated CdZnTe substrates and quantum wires fabricated by dry etching techniques from (CdTe)/(MnTe) superlattices (SLs), which were grown by a combination of molecular beam and atomic layer epitaxy, were investigated with respect to their structural properties. The SLs were grown pseudomorphically on Cd 0.96Zn 0.04Te (001) oriented substrates. X-ray reciprocal space mapping around (004) and (115) reciprocal lattice points was used to measure the periods both along the growth and the lateral corrugation direction. The arrays were defined by holographic lithography and reactive ion etching with a typical period of about 400 nm. For the analysis of the corrugations, a kinematical X-ray diffraction model is used which yields their geometrical shape and also informations on the crystalline damage. Furthermore, it turns out that the reactive ion etching process causes an increase of the mean SL lattice constant of about 0.1% to 0.15% along the growth direction.